Almost half of UK organisations have been compromised in the past two years using phishing attacks, despite high levels of cyber awareness and training, research shows.

Phihing attacks aimed at stealing legitimate user credentials have been used in the past 24 months to compromise 45% of UK organisations, according to research on behalf of cyber security firm Sophos

Just over half (54%) of more than 900 IT directors polled in Western Europe said they had identified instances of employees replying to unsolicited emails or clicking on links contained within them, revealed a poll conducted by Sapio Research. The study revealed that larger businesses are most likely to have been compromised by phishing attacks, despite also being most likely to conduct phishing and cyber threat awareness training.

Although organisations in the UK fell victim to phishing attacks at a similar rate to those in France (49%) and the Netherlands (44%), those in Ireland performed significantly better. Just 25% of Irish respondents said they had fallen victim to phishing in the past two years.

Across all respondents, 56% of companies employing between 500 and 750 people were identified as phishing victims in the past two years, while two-thirds (65%) had identified instances of employees replying to unsolicited emails or clicking on links contained within them.

By comparison, just 25% firms with fewer than 250 people and 36% of organisations with between 250 and 499 employees had been compromised by phishing in the same period.

Half of firms with fewer than 250 people offered training to help employees spot attacks, compared with 78% of those with between 500 and 1,000 people. And 79% of UK companies conduct regular cyber threat awareness training already, while 18% said they plan to offer it in the future.

Adam Bradley, UK managing director at Sophos, said criminals are adept at using social engineering to exploit human weakness, so while well-trained employees are an excellent deterrent, even the best user can slip up.

“Organisations need to ensure employees remain vigilant to the threat posed by phishing attacks and ongoing training should be part of that to spot check employees and ensure they respond correctly and continue to follow the guidelines they’ve been given.”

According to Bradley, phishing is one of the most common routes of entry for cyber criminals. “As organisations grow, their risk of becoming a victim also increases as they become more lucrative targets and provide hackers with more potential points of failure.

“Given the frequency of these attacks, organisations that don’t have basic infrastructure in place to spot people engaging with potentially harmful emails and whether their systems are compromised are likely to encounter some really significant problems,” he said.

Organisations should block malicious links, attachments and imposters before they reach users’ inboxes, said Bradley, and use the latest cyber security tools to stop ransomware and other advanced threats from running on devices even if a user clicks a malicious link or opens an infected attachment.